7.3.2 Cardiac Cycle

    Cards (13)

    • The cardiac cycle is the complete sequence of events that occur during one heartbeat
    • During diastole, atrial and ventricular pressure are low.
    • During systole, atrial pressure remains low while ventricular pressure increases dramatically
    • The cardiac cycle consists of two main phases: diastole and systole.
    • Stages of the cardiac cycle in order
      1️⃣ Atrial systole
      2️⃣ Ventricular systole
      3️⃣ Diastole
    • During atrial systole, atrial pressure increases briefly while ventricular pressure remains low
    • During ventricular systole, blood is forced into the aorta and pulmonary artery.
    • The atrioventricular valves include the mitral valve on the left and the tricuspid valve on the right
    • The semilunar valves prevent blood from flowing back into the ventricles during diastole.
    • Match the valve type with its function:
      Atrioventricular Valves ↔️ Prevent backflow into atria
      Semilunar Valves ↔️ Prevent backflow into ventricles
    • The sinoatrial (SA) node acts as the natural pacemaker
    • Sympathetic nerves decrease heart rate and contractility.
      False
    • Epinephrine and norepinephrine are hormones that increase heart rate and force of contraction